Which of the following describes the maximum stress before permanent deformation occurs?

The yield strength is defined as the maximum stress that a material can withstand before undergoing permanent deformation. When a material is subjected to increasing stress, it may initially deform elastically, meaning it will return to its original shape when the stress is removed. However, once the applied stress exceeds the yield strength, the material will no longer return to its original shape after the load is removed, resulting in irreversible deformation.

Understanding yield strength is crucial for selecting materials in engineering applications, ensuring that components can withstand operational stresses without incurring permanent damage. It essentially indicates the reliability and safety of a material under specified loading conditions.

The other terms, while related to stress and deformation, do not specifically capture the point at which permanent deformation begins. For example, tensile strength refers to the maximum stress a material can withstand while being stretched or pulled before failure occurs, which is beyond the yield point. The elastic limit is closely related to yield strength but may not include all factors considered under yield strength in a practical sense. Breaking point refers to the point at which the material ultimately fails or fractures, which is distinct from yield strength as it involves complete loss of structural integrity.